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Updated: Aug 9, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
11:45

Quantifying Agonist Activity at G Protein-coupled Receptors

Published on: December 26, 2011

The carboxyl terminus of mouse delta-opioid receptor is not required for agonist-dependent activation

X Zhu1, C Wang, Z Cheng

  • 1Shanghai Research Center of Life Sciences, Peoples' Republic of China.

Biochemical and Biophysical Research Communications
|March 17, 1997
PubMed

Insights

The delta opioid receptor's C-terminus is not essential for its function. This finding impacts understanding opioid receptor (OR) structure-function relationships and drug development.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Neuroscience

Background:

  • Opiate drugs exert effects via opioid receptors (ORs).
  • ORs activate inhibitory G proteins (Gi), decreasing cAMP levels.
  • Understanding OR structure-function is crucial for drug development.

Purpose of the Study:

  • To investigate the role of the delta opioid receptor's C-terminus.
  • To determine if the C-terminus is essential for receptor function.

Main Methods:

  • Ectopic expression of wild-type and C-terminally truncated delta OR in CHO cells.
  • Comparison of ligand binding potency (DPDPE, DSLET, DAGO, U-50488).
  • Assessment of membrane localization and signal transduction.

Main Results:

  • The C-terminus is not essential for plasma membrane targeting.
  • Ligand specificity remains intact in the truncated receptor.
  • Agonist-dependent activation is not dependent on the C-terminus.

Conclusions:

  • The C-terminus of the delta opioid receptor is dispensable for key functions.
  • These findings contribute to understanding OR structure-activity relationships.

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